Dead acacia trees remain standing in a dry, cracked portion of Africa's Namib Desert. Because the desert is so dry, many well preserved human artifacts and ancient fossils can be found there.

Photograph from Natphotos/Getty Images

Growing Deserts

It's hard to imagine that global warming would have much effect on the world's already hot deserts. But even small changes in temperature or precipitation could drastically impact plants and animals living in the desert. In some cases global warming is predicted to increase the area of deserts, which already cover a quarter of Earth.

Human activities such as firewood gathering and the grazing of animals are also converting semiarid regions into deserts, a process known as desertification. Population growth and greater demand for land are serious obstacles in the effort to combat this problem.

Threats

Global warming is increasing the incidence of drought, which dries up water holes.

Higher temperatures may produce an increasing number of wildfires that alter desert landscapes by eliminating slow-growing trees and shrubs and replacing them with fast-growing grasses.

Irrigation used for agriculture, may in the long term, lead to salt levels in the soil that become too high to support plants.

Grazing animals can destroy many desert plants and animals.

Potassium cyanide used in gold mining may poison wildlife.

Off-road vehicles, when used irresponsibly, can cause irreparable damage to desert habitats.

Oil and gas production may disrupt sensitive habitat.

Nuclear waste may be dumped in deserts, which have also been used as nuclear testing grounds.

Solutions

More efficiently use existing water resources and better control salinization to improve arid lands.

Find new ways to rotate crops to protect the fragile soil.

Plant sand-fixing bushes and trees.

Plant leguminous plants, which extract nitrogen from the air and fix it in the ground, to restore soil fertility.

Use off-road vehicles only on designated trails and roadways

Dig artificial grooves in the ground to retain rainfall and trap windblown seeds.